can i unwarp a cylinder to flat plane object?
Think of it backwards. Use a simple deform modifier and an empty to control it.

Start with a plane, subdivide it and add a simple deform modifier.



Add an empty. Rotate it 90 degrees on the X axis.



Select the plane, set the simple deform modifier to bend, select the empty as the origin axis and set the angle to 360



Then you can just play with the angle on the modifier to do whatever it is that you want to do.